title: Origin of tripronucleate zygotes after intracytoplasmic sperm injection.
abstract: Zygotes morphologically classified as tripronuclear (3PN) after intracytoplasmic sperm injection (ICSI), which are thought to be digynic in their origin, were studied by fluorescent in-situ hybridization (FISH). FISH results allowed us to assess the suspected ploidy after morphological evaluation of the zygote and to determine the origin of the third pronuclei. Our results show that, firstly, 36% of those zygotes classified as 3PN following their morphological evaluation were, in fact, diploid, and secondly, the main cause for triploidy after ICSI is the non-extrusion of the second polar body.
authors.affiliation: Unitat de Biologia Celular, Facultat de Ciències, Universitat Autònoma de Barcelona, Bellaterra, Spain.
authors.forename: M
authors.initials: M
authors.lastname: Grossmann
authors.forename: J M
authors.initials: JM
authors.lastname: Calafell
authors.forename: N
authors.initials: N
authors.lastname: Brandy
authors.forename: J A
authors.initials: JA
authors.lastname: Vanrell
authors.forename: C
authors.initials: C
authors.lastname: Rubio
authors.forename: A
authors.initials: A
authors.lastname: Pellicer
authors.forename: J
authors.initials: J
authors.lastname: Egozcue
authors.forename: F
authors.initials: F
authors.lastname: Vidal
authors.forename: J
authors.initials: J
authors.lastname: Santaló
mesh_terms: D002467:Cell Nucleus / Q000648:ultrastructure*; D002887:Chromosomes, Human, Pair 18; D005260:Female; D005307:Fertilization in Vitro / Q000379:methods*; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D008297:Male; D008845:Microinjections; D011003:Ploidies; D014314:Trisomy; D014960:X Chromosome; D014998:Y Chromosome; D015053:Zygote / Q000648:ultrastructure*